More particularly, the method of the invention for centering steerable axles of a bogie is applicable to a bogie having two steerable axles. For example, such a bogie comprises a frame connected to each axle via two axle boxes and via primary suspension means formed of deformable resilient blocks.
In such prior art bogies, the axles are steered by means of actuators controlled by track sensors. Under the action of the actuators, the resilient primary suspension means become deformed so as to enable the axle to take up a radial position in a curve in the track. The axles are usually steered by flexible suspension means. The axles are then kept stable along straight stretches of the track by means other than the flexible suspension means.
The advantage of steerable-axle bogies, in particular for subway and tramway networks, is that they reduce the adverse effects caused by having metal-on-metal contact, namely: squealing, wear on rails and on wheels, and vibrations transmitted through the ground to buildings.